Single inlet oxygen burner for metal making

Abstract

The present disclosure describes a metal making burner in fluid communication with a gas inlet and comprising an oxygen inlet valve that provides control of oxygen flow to two different discharge lines, such as a main line and a shroud line. This allows distinct “modes” of operation, utilizing only the flow from the single oxygen supply as the control method. The apparatus includes a moving piston with ports therein that meter flow to both discharge lines when the ports line up with a separate set of ports in a cylinder that receives the piston. At low or no pressure from the gas inlet, flow rates follow one ratio of flows between the discharge lines. As pressure from a gas inlet changes in the burner, the piston moves and realigns the ports (opening or closing some of the ports), which results in a different ratio of flows between the discharge lines.

What is claimed is: 
     
       1. A burner apparatus, the apparatus comprising:
 a tubular body having a first end and a second end; 
 a first oxygen circuit disposed inside of the tubular body and having an outlet at the first end of the tubular body; 
 a second oxygen circuit attached to the outside of the tubular body, wherein the tubular body includes openings connected with the second oxygen circuit; 
 a valve disposed in the tubular body proximate to the second end of the tubular body, the valve comprising:
 a hollow piston, comprising:
 a piston wall having a first end and a second end; and 
 an end cap connected to the first end of the piston wall; 
 wherein the piston wall defines a plurality of piston ports; 
 
 a cylinder configured to receive the hollow piston, wherein the cylinder defines a plurality of cylinder ports aligned with an inlet of the first oxygen circuit and an inlet of the second oxygen circuit; 
 a biasing member in physical communication with the hollow piston and the tubular body and responsive to oxygen pressure applied at the second end of the tubular body; 
 and 
 wherein, when the hollow piston is positioned at different points within the cylinder, one or more of the piston ports align with one or more of the cylinder ports. 
 
 
     
     
       2. The apparatus of  claim 1 , wherein the plurality of piston ports comprise one or more ports configured to align with the first oxygen circuit and one or more ports configured to align with the second oxygen circuit. 
     
     
       3. The apparatus of  claim 2 , wherein a combined cross-sectional area of the one or more ports configured to align with the first oxygen circuit is equal to a combined cross-sectional area of the one or more ports configured to align with the second oxygen circuit. 
     
     
       4. The apparatus of  claim 2 , wherein the one or more ports configured to align with the second oxygen circuit comprise two or more ports of equal cross-sectional area. 
     
     
       5. The apparatus of  claim 1 , the tubular body further comprising: a restraint member disposed on an inside of the tubular body; and the piston wall comprising a channel configured to receive the restraint member such that the restraint member limits the travel of the hollow piston to a selected distance from the second end. 
     
     
       6. The apparatus of  claim 1 , wherein the first oxygen circuit is a main oxygen circuit and the second oxygen circuit is a shroud oxygen circuit. 
     
     
       7. The apparatus of  claim 1 , wherein the biasing member is a spring. 
     
     
       8. The apparatus of  claim 1 , further comprising a gas tube connected to the tubular body to provide fuel to the burner apparatus. 
     
     
       9. The apparatus of  claim 1 , wherein the plurality of piston ports comprises at least three piston ports and the plurality of cylinder ports comprises at least two cylinder ports. 
     
     
       10. A method of controlling oxygen pressure in a burner apparatus, the burner comprising:
 a tubular body having a first end and second end; 
 a first oxygen circuit disposed inside of the tubular body with an outlet at the first end; 
 a second oxygen circuit attached to the outside of the tubular body, where the tubular body includes openings connected with the second oxygen circuit; 
 a valve disposed in the tubular body proximate to the second end, the valve comprising:
 a hollow piston, comprising:
 a piston wall with a first end and a second end; and 
 an end cap connected to the first end of the piston wall; 
 wherein the piston wall comprises a plurality of piston ports; 
 
 a cylinder configured to receive the hollow piston, wherein the cylinder has a plurality of cylinder ports aligned with an inlet of the first oxygen circuit and an inlet of the second oxygen circuit; 
 a biasing member in physical communication with the hollow piston and the tubular body and responsive to oxygen pressure applied at the second end; and 
 wherein, when the hollow piston is positioned at different points within the cylinder, one or more of the piston ports align with one or more of the cylinder ports; 
 
 the method comprising the steps of:
 applying oxygen to the valve at a first pressure wherein the hollow piston is in a first position associated with a first ratio between an output flow from the first oxygen circuit and an output flow form the second oxygen circuit; and 
 changing the first pressure to a second pressure causing the hollow piston to move to a second position associated with a second ratio between the output flow from the first oxygen circuit and the output flow from the second oxygen circuit. 
 
 
     
     
       11. The method of  claim 10 , wherein the first ratio is 50:50, and the first pressure is 10 psi (69 kPa) or less. 
     
     
       12. The method of  claim 10 , wherein the second ratio is 90:10, and the second pressure is 25 psi (172 kPa) or greater. 
     
     
       13. The method of  claim 10 , wherein the first position is about 2 inches (5.1 cm) from the second position. 
     
     
       14. The method of  claim 10 , wherein the first oxygen circuit is a main oxygen circuit and the second oxygen circuit is a shroud oxygen circuit. 
     
     
       15. The method of  claim 10 , wherein the biasing member is a spring. 
     
     
       16. The method of  claim 10 , further comprising a gas tube connected to the tubular body to provide fuel to the burner apparatus. 
     
     
       17. The method of  claim 10 , wherein the plurality of piston ports comprises at least three piston ports and the plurality of cylinder ports comprises at least two cylinder ports. 
     
     
       18. The method of  claim 10 , the method further comprising the step of changing the second pressure to a third pressure causing the hollow piston to move to a third position associated with a third ratio between the output flow from the first oxygen circuit and the output flow from the second oxygen circuit.